diff --git a/src/testdir/test_visual.vim b/src/testdir/test_visual.vim
index 9ca0fa9..b438fa1 100644
--- a/src/testdir/test_visual.vim
+++ b/src/testdir/test_visual.vim
@@ -1280,11 +1280,13 @@
 
 func Test_visual_block_append_invalid_char()
   " this was going over the end of the line
+  set isprint=@,161-255
   new
   call setline(1, ['	   let xxx', 'xxxxx', 'xxxxxxxxxxx'])
   exe "normal 0\<C-V>jjA-\<Esc>"
   call assert_equal(['	-   let xxx', 'xxxxx   -', 'xxxxxxxx-xxx'], getline(1, 3))
   bwipe!
+  set isprint&
 endfunc
 
 func Test_visual_reselect_with_count()